Displaying 20 results from an estimated 4000 matches similar to: "efficient writing of calculation involving each element of 2 data frames."
2008 Feb 22
2
Corrected : Efficient writing of calculation involving each element of 2 data frames
Hi
I have 2 data.frames each of the same number of rows (approximately 30000 or
more entries).
They also have the same number of columns, lets say 2.
One column has the date, the other column has a double precision number. Let
the column names be V1, V2.
Now I want to calculate the correlation of the 2 sets of data, for the last
100 days for every day available in the data.frames.
My code looks
2005 Jun 09
1
Subassignments involving NAs in data frames
I'm seeing some inconsistent behavior when re-assigning values in a data
frame. The first assignment turns all of the 0s in my data frame to 2s,
the second fails to do so.
> df1 <- data.frame(a = c(NA, 0, 3, 4))
> df2 <- data.frame(a = c(NA, 0, 0, 4))
> df1[df1 == 0] <- 2 ## Works
> df2[df2 == 0] <- 2
Error: NAs are not allowed in subscripted assignments
Checking an
2011 Dec 01
1
efficient ways to dynamically grow a dataframe
Hi,
I'm trying to write a small microsimulation in R: that is, I have a
dataframe with info on N individuals for the base-year and I have to
grow it dynamically for T periods:
df = data.frame(
id = 1:N,
x =....
)
The most straightforward way to solve the problem that came to my mind
is to create for every period a new dataframe:
for(t in 1:T){
for(i in 1:N){
row = data.frame(
id =
2010 Nov 11
4
How to get a specific named element in a nested list
Hello,
I have a nested named list structure, like the following:
x <- list(
list(
list(df1,df2)
list(df3,
list(df4,df5))
list(df6,df7)))
with df1...d7 as data frames. Every data frame is named.
Is there a way to get a specific named element in x?
so, for example,
x[[c("df5")]] gives me the data frame 5?
Thank you in advance!
Best,
Friedericksen
2011 Jan 27
2
identifying when one element of a row has a positive number
Hello,
I am not sure where to begin with this problem or what to search for
in r-help. I just don't know what to call this.
If I have 5 columns, the first 2 are the x,y, locations and the last
three are variables about those locations.
x<-seq(1860,1950,by=10)
y<-seq(-290,-200,by=10)
ANN<-c(3,0,0,0,1,0,1,1,0,0)
CTA<-c(0,1,0,0,0,0,1,0,0,2)
GLM<-c(0,0,2,0,0,0,0,1,0,0)
2008 Sep 14
5
difference of two data frames
Hello
I have 2 data frames DF1 and DF2 where DF2 is a subset of DF1:
DF1= data.frame(V1=1:6, V2= letters[1:6])
DF2= data.frame(V1=1:3, V2= letters[1:3])
How do I create a new data frame of the difference between DF1 and DF2
newDF=data.frame(V1=4:6, V2= letters[4:6])
In my real data, the rows are not in order as in the example I provided.
Thanks much
Joseph
[[alternative HTML version
2011 Aug 18
2
Best way/practice to create a new data frame from two given ones with last column computed from the two data frames?
Dear expeRts,
What is the best approach to create a third data frame from two given ones, when
the new/third data frame has last column computed from the last columns of the two given
data frames?
## Okay, sounds complicated, so here is an example. Assume we have the two data frames:
df1 <- data.frame(Year=rep(2001:2010, each=2), Group=c("Group 1","Group 2"), Value=1:20)
2012 Jul 11
4
Help with loop
Hi,
I have two dataframes:
The first, df1, contains some missing data:
cola colb colc cold cole
1 NA 5 9 NA 17
2 NA 6 NA 14 NA
3 3 NA 11 15 19
4 4 8 12 NA 20
The second, df2, contains the following:
cola colb colc cold cole
1 1.4 0.8 0.02 1.6 0.6
I'm wanting all missing data in df1$cola to be replaced by the value of
df2$cola.
2013 Feb 26
2
merging or joining 2 dataframes: merge, rbind.fill, etc.?
#I want to "merge" or "join" 2 dataframes (df1 & df2) into a 3rd
(mydf). I want the 3rd dataframe to contain 1 row for each row in df1
& df2, and all the columns in both df1 & df2. The solution should
"work" even if the 2 dataframes are identical, and even if the 2
dataframes do not have the same column names. The rbind.fill function
seems to work. For
2008 Feb 10
11
data frame question
Hello
I have 2 data frames df1 and df2. I would like to create a
new data frame new_df which will contain only the common rows based on the first 2
columns (chrN and start). The column score in the new data frame
should
be replaced with a column containing the average score (average_score) from df1
and df2.
df1= data.frame(chrN= c(“chr1”, “chr1”, “chr1”, “chr1”, “chr2”,
“chr2”, “chr2”),
2013 Jan 02
2
rbind: inconsistent behaviour with empty data frames?
The rbind on empty and nonempty data frames behaves inconsistently. I am
not sure if by design.
In the first example, first row is deleted, which may or may not be on
purpose:
df1 <- data.frame()
df2 <- data.frame(foo=c(1, 2), bar=c("a", "b"))
rbind(df1, df2)
foo bar
2 2 b
Now if we continue:
df1 <- data.frame(matrix(0, 0, 2))
names(df1) <- names(df2)
2009 Jan 21
3
merging several dataframes from a list
Hi there,
I have a list of dataframes (generated by reading multiple files) and all
dataframes are comparable in dimension and column names. They also have a
common column, which, I'd like to use for merging. To give a simple example of
what I have:
df1 <- data.frame(c(LETTERS[1:5]), c(2,6,3,1,9))
names(df1) <- c("pos", "data")
df3 <- df2 <- df1
df2$data
2010 Dec 16
2
Compare two dataframes
Hello,
I have two dataframes DF1 and DF2 that should be identical but are not
(DF1 has some rows that aren't in DF2, and vice versa). I would like
to produce a new dataframe DF3 containing rows in DF1 that aren't in
DF2 (and similarly DF4 would contain rows in DF2 that aren't in DF1).
I have a solution for this problem (see self contained example below)
but it's awkward and
2012 Jun 03
2
merging single column from different dataframe
Hi all,
probably really simple to solve, but having no background in programming I
haven't been able to figure this out: I have two dataframes like
df1 <- data.frame(names1=c('aa','ab', 'ac', 'ad'), var1=c(1,5,7,12))
df2 <- data.frame(names2=c('aa', 'ab', 'ac', 'ad', 'ae'),
var2=c(3,6,9,12,15))
Now I want merge
2016 Jun 23
2
Asignar a un dataframe un id de otro dataframe en función de intervalos con fechas
Hola a todxs,
No encuentro la manera de hacer algo que aparentemente parece muy sencillo:
Tengo dos dataframe, en el primero tengo una serie de códigos con hora de
inicio y hora de fin y en el segundo otros códigos asociados a una hora; Lo
que necesito es crear una nueva variable en el segundo data frame que
indique a qué intervalo del primer data frame (df1$id) pertenece cada nivel
del segundo
2017 Jul 13
2
about plotting a special case
Thanks, Jim. The code works, but I don't understand why you use q1090 <-
quantile(DF1$B, probs=c()), rather than DF1$A? Also, how to add a legend
for both points DF1 and DF2?
On Wed, Jul 12, 2017 at 8:25 PM, Jim Lemon <drjimlemon at gmail.com> wrote:
> Hi lily,
> Here is the first plot:
>
> plot(DF1$A,DF1$B,pch=19,col="red")
> meanA<-mean(DF1$A)
>
2011 Apr 30
3
indexing into a data.frame using another data.frame that also contains values for replacement
Hello all,
I have a quandry I have been scratching my head about for a
while. I've searched the manual and the web and have not been able to
find an acceptable result, so I am hoping for some help.
I have two data frames and I want to index into the first using
the second, and replace the specific values I have indexed with more
values from the second data.frame. I can do this
2012 Aug 14
4
Subsetting rows by multiple levels of selected values
Dear list,
Let's say we have a data frame as follows,
>expand.grid(a=1:5,b=c(1,5,10,20),DV=c(0.1,0.2,0.3))->df1
>df1$DV<-rgamma(60,shape=10)
columns a and b are two levels. DV is the column with values we are
interested in.
Then another data frame df2 with values as follows
data.frame(a=c(2,2,3,4,5),b=c(5,10,1,5,20))->df2
Now I want to a subset of df1 that match df2 at the
2010 Nov 05
4
assignment operator saving factor level as number
Hi all,
I have a dataframe (df1) that I am trying to select values from to a second
dataframe that at the current time is only for the selected items from df1
(df2). The values that I am trying to save from df1 are factors with
alphanumeric names
df1 looks like this:
'data.frame': 3014 obs. of 13 variables:
$ Num : int 1 1 1 2 2 2 3 3 3 4 ...
$ Tag_Num : int 1195
2007 May 05
1
loop in function
Dear Mailing-List,
I think this is a newbie question. However, i would like to integrate a
loop in the function below. So that the script calculates for each
variable within the dataframe df1 the connecting data in df2. Actually it
takes only the first row. I hope that's clear. My goal is to apply the
function for each data in df1. Many thanks in advance. An example is as
follows:
df1